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{
"language": "Solidity",
"sources": {
"/Users/koloale/orion-projects/orion-exchange_dev/contracts/utils/orionpool/core/OrionPoolV2ERC20.sol": {
"content": "//import './interfaces/IOrionPoolV2ERC20.sol';\nimport '@openzeppelin/contracts/math/SafeMath.sol';\n\ncontract OrionPoolV2ERC20 {\n using SafeMath for uint;\n\n string public constant name = 'OrionPool V2';\n string public constant symbol = 'UNI-V2';\n uint8 public constant decimals = 18;\n uint public totalSupply;\n mapping(address => uint) public balanceOf;\n mapping(address => mapping(address => uint)) public allowance;\n\n bytes32 public DOMAIN_SEPARATOR;\n // keccak256(\"Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)\");\n bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;\n mapping(address => uint) public nonces;\n\n event Approval(address indexed owner, address indexed spender, uint value);\n event Transfer(address indexed from, address indexed to, uint value);\n\n constructor() public {\n uint chainId;\n assembly {\n chainId := chainid()\n }\n DOMAIN_SEPARATOR = keccak256(\n abi.encode(\n keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),\n keccak256(bytes(name)),\n keccak256(bytes('1')),\n chainId,\n address(this)\n )\n );\n }\n\n function _mint(address to, uint value) internal {\n totalSupply = totalSupply.add(value);\n balanceOf[to] = balanceOf[to].add(value);\n emit Transfer(address(0), to, value);\n }\n\n function _burn(address from, uint value) internal {\n balanceOf[from] = balanceOf[from].sub(value);\n totalSupply = totalSupply.sub(value);\n emit Transfer(from, address(0), value);\n }\n\n function _approve(address owner, address spender, uint value) private {\n allowance[owner][spender] = value;\n emit Approval(owner, spender, value);\n }\n\n function _transfer(address from, address to, uint value) private {\n balanceOf[from] = balanceOf[from].sub(value);\n balanceOf[to] = balanceOf[to].add(value);\n emit Transfer(from, to, value);\n }\n\n function approve(address spender, uint value) external returns (bool) {\n _approve(msg.sender, spender, value);\n return true;\n }\n\n function transfer(address to, uint value) external returns (bool) {\n _transfer(msg.sender, to, value);\n return true;\n }\n\n function transferFrom(address from, address to, uint value) external returns (bool) {\n if (allowance[from][msg.sender] != uint(-1)) {\n allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);\n }\n _transfer(from, to, value);\n return true;\n }\n\n function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {\n require(deadline >= block.timestamp, 'OrionPoolV2: EXPIRED');\n bytes32 digest = keccak256(\n abi.encodePacked(\n '\\x19\\x01',\n DOMAIN_SEPARATOR,\n keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))\n )\n );\n address recoveredAddress = ecrecover(digest, v, r, s);\n require(recoveredAddress != address(0) && recoveredAddress == owner, 'OrionPoolV2: INVALID_SIGNATURE');\n _approve(owner, spender, value);\n }\n}\n"
},
"/Users/koloale/orion-projects/orion-exchange_dev/contracts/utils/orionpool/core/OrionPoolV2Pair.sol": {
"content": "//import './interfaces/IOrionPoolV2Pair.sol';\nimport './OrionPoolV2ERC20.sol';\nimport './libraries/Math.sol';\nimport './libraries/UQ112x112.sol';\nimport '@openzeppelin/contracts/token/ERC20/IERC20.sol';\nimport './interfaces/IOrionPoolV2Factory.sol';\nimport './interfaces/IOrionPoolV2Callee.sol';\n\ncontract OrionPoolV2Pair is OrionPoolV2ERC20 {\n using SafeMath for uint;\n using UQ112x112 for uint224;\n\n uint public constant MINIMUM_LIQUIDITY = 10**3;\n bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));\n\n address public factory;\n address public token0;\n address public token1;\n\n uint112 private reserve0; // uses single storage slot, accessible via getReserves\n uint112 private reserve1; // uses single storage slot, accessible via getReserves\n uint32 private blockTimestampLast; // uses single storage slot, accessible via getReserves\n\n uint public price0CumulativeLast;\n uint public price1CumulativeLast;\n uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event\n\n uint private unlocked = 1;\n modifier lock() {\n require(unlocked == 1, 'OrionPoolV2: LOCKED');\n unlocked = 0;\n _;\n unlocked = 1;\n }\n\n function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {\n _reserve0 = reserve0;\n _reserve1 = reserve1;\n _blockTimestampLast = blockTimestampLast;\n }\n\n function _safeTransfer(address token, address to, uint value) private {\n (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));\n require(success && (data.length == 0 || abi.decode(data, (bool))), 'OrionPoolV2: TRANSFER_FAILED');\n }\n\n event Mint(address indexed sender, uint amount0, uint amount1);\n event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);\n event Swap(\n address indexed sender,\n uint amount0In,\n uint amount1In,\n uint amount0Out,\n uint amount1Out,\n address indexed to\n );\n event Sync(uint112 reserve0, uint112 reserve1);\n\n constructor() public {\n factory = msg.sender;\n }\n\n // called once by the factory at time of deployment\n function initialize(address _token0, address _token1) external {\n require(msg.sender == factory, 'OrionPoolV2: FORBIDDEN'); // sufficient check\n token0 = _token0;\n token1 = _token1;\n }\n\n // update reserves and, on the first call per block, price accumulators\n function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {\n require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'OrionPoolV2: OVERFLOW');\n uint32 blockTimestamp = uint32(block.timestamp % 2**32);\n uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired\n if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {\n // * never overflows, and + overflow is desired\n price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;\n price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;\n }\n reserve0 = uint112(balance0);\n reserve1 = uint112(balance1);\n blockTimestampLast = blockTimestamp;\n emit Sync(reserve0, reserve1);\n }\n\n // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)\n function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {\n address feeTo = IOrionPoolV2Factory(factory).feeTo();\n feeOn = feeTo != address(0);\n uint _kLast = kLast; // gas savings\n if (feeOn) {\n if (_kLast != 0) {\n uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));\n uint rootKLast = Math.sqrt(_kLast);\n if (rootK > rootKLast) {\n uint numerator = totalSupply.mul(rootK.sub(rootKLast));\n uint denominator = rootK.mul(2).add(rootKLast);\n uint liquidity = numerator / denominator;\n if (liquidity > 0) _mint(feeTo, liquidity);\n }\n }\n } else if (_kLast != 0) {\n kLast = 0;\n }\n }\n\n // this low-level function should be called from a contract which performs important safety checks\n function mint(address to) external lock returns (uint liquidity) {\n (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings\n uint balance0 = IERC20(token0).balanceOf(address(this));\n uint balance1 = IERC20(token1).balanceOf(address(this));\n uint amount0 = balance0.sub(_reserve0);\n uint amount1 = balance1.sub(_reserve1);\n\n bool feeOn = _mintFee(_reserve0, _reserve1);\n uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee\n if (_totalSupply == 0) {\n liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);\n _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens\n } else {\n liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);\n }\n require(liquidity > 0, 'OrionPoolV2: INSUFFICIENT_LIQUIDITY_MINTED');\n _mint(to, liquidity);\n\n _update(balance0, balance1, _reserve0, _reserve1);\n if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date\n emit Mint(msg.sender, amount0, amount1);\n }\n\n // this low-level function should be called from a contract which performs important safety checks\n function burn(address to) external lock returns (uint amount0, uint amount1) {\n (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings\n address _token0 = token0; // gas savings\n address _token1 = token1; // gas savings\n uint balance0 = IERC20(_token0).balanceOf(address(this));\n uint balance1 = IERC20(_token1).balanceOf(address(this));\n uint liquidity = balanceOf[address(this)];\n\n bool feeOn = _mintFee(_reserve0, _reserve1);\n uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee\n amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution\n amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution\n require(amount0 > 0 && amount1 > 0, 'OrionPoolV2: INSUFFICIENT_LIQUIDITY_BURNED');\n _burn(address(this), liquidity);\n _safeTransfer(_token0, to, amount0);\n _safeTransfer(_token1, to, amount1);\n balance0 = IERC20(_token0).balanceOf(address(this));\n balance1 = IERC20(_token1).balanceOf(address(this));\n\n _update(balance0, balance1, _reserve0, _reserve1);\n if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date\n emit Burn(msg.sender, amount0, amount1, to);\n }\n\n // this low-level function should be called from a contract which performs important safety checks\n function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {\n require(amount0Out > 0 || amount1Out > 0, 'OrionPoolV2: INSUFFICIENT_OUTPUT_AMOUNT');\n (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings\n require(amount0Out < _reserve0 && amount1Out < _reserve1, 'OrionPoolV2: INSUFFICIENT_LIQUIDITY');\n\n uint balance0;\n uint balance1;\n { // scope for _token{0,1}, avoids stack too deep errors\n address _token0 = token0;\n address _token1 = token1;\n require(to != _token0 && to != _token1, 'OrionPoolV2: INVALID_TO');\n if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens\n if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens\n if (data.length > 0) IOrionPoolV2Callee(to).orionpoolV2Call(msg.sender, amount0Out, amount1Out, data);\n balance0 = IERC20(_token0).balanceOf(address(this));\n balance1 = IERC20(_token1).balanceOf(address(this));\n }\n uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;\n uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;\n require(amount0In > 0 || amount1In > 0, 'OrionPoolV2: INSUFFICIENT_INPUT_AMOUNT');\n { // scope for reserve{0,1}Adjusted, avoids stack too deep errors\n uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));\n uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));\n require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'OrionPoolV2: K');\n }\n\n _update(balance0, balance1, _reserve0, _reserve1);\n emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);\n }\n\n // force balances to match reserves\n function skim(address to) external lock {\n address _token0 = token0; // gas savings\n address _token1 = token1; // gas savings\n _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));\n _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));\n }\n\n // force reserves to match balances\n function sync() external lock {\n _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);\n }\n}\n"
},
"/Users/koloale/orion-projects/orion-exchange_dev/contracts/utils/orionpool/core/interfaces/IOrionPoolV2Callee.sol": {
"content": "interface IOrionPoolV2Callee {\n function orionpoolV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;\n}\n"
},
"/Users/koloale/orion-projects/orion-exchange_dev/contracts/utils/orionpool/core/interfaces/IOrionPoolV2Factory.sol": {
"content": "interface IOrionPoolV2Factory {\n event PairCreated(address indexed token0, address indexed token1, address pair, uint);\n\n function feeTo() external view returns (address);\n function feeToSetter() external view returns (address);\n\n function getPair(address tokenA, address tokenB) external view returns (address pair);\n function allPairs(uint) external view returns (address pair);\n function allPairsLength() external view returns (uint);\n\n function createPair(address tokenA, address tokenB) external returns (address pair);\n\n function setFeeTo(address) external;\n function setFeeToSetter(address) external;\n}\n"
},
"/Users/koloale/orion-projects/orion-exchange_dev/contracts/utils/orionpool/core/libraries/Math.sol": {
"content": "// a library for performing various math operations\n\nlibrary Math {\n function min(uint x, uint y) internal pure returns (uint z) {\n z = x < y ? x : y;\n }\n\n // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)\n function sqrt(uint y) internal pure returns (uint z) {\n if (y > 3) {\n z = y;\n uint x = y / 2 + 1;\n while (x < z) {\n z = x;\n x = (y / x + x) / 2;\n }\n } else if (y != 0) {\n z = 1;\n }\n }\n}\n"
},
"/Users/koloale/orion-projects/orion-exchange_dev/contracts/utils/orionpool/core/libraries/UQ112x112.sol": {
"content": "// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))\n\n// range: [0, 2**112 - 1]\n// resolution: 1 / 2**112\n\nlibrary UQ112x112 {\n uint224 constant Q112 = 2**112;\n\n // encode a uint112 as a UQ112x112\n function encode(uint112 y) internal pure returns (uint224 z) {\n z = uint224(y) * Q112; // never overflows\n }\n\n // divide a UQ112x112 by a uint112, returning a UQ112x112\n function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {\n z = x / uint224(y);\n }\n}\n"
},
"@openzeppelin/contracts/math/SafeMath.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.0 <0.8.0;\n\n/**\n * @dev Wrappers over Solidity's arithmetic operations with added overflow\n * checks.\n *\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\n * in bugs, because programmers usually assume that an overflow raises an\n * error, which is the standard behavior in high level programming languages.\n * `SafeMath` restores this intuition by reverting the transaction when an\n * operation overflows.\n *\n * Using this library instead of the unchecked operations eliminates an entire\n * class of bugs, so it's recommended to use it always.\n */\nlibrary SafeMath {\n /**\n * @dev Returns the addition of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n uint256 c = a + b;\n if (c < a) return (false, 0);\n return (true, c);\n }\n\n /**\n * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n if (b > a) return (false, 0);\n return (true, a - b);\n }\n\n /**\n * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n *\n * _Available since v3.4._\n */\n function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n // Gas optimization: this is cheaper than requiring 'a' not being zero, but the\n // benefit is lost if 'b' is also tested.\n // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n if (a == 0) return (true, 0);\n uint256 c = a * b;\n if (c / a != b) return (false, 0);\n return (true, c);\n }\n\n /**\n * @dev Returns the division of two unsigned integers, with a division by zero flag.\n *\n * _Available since v3.4._\n */\n function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n if (b == 0) return (false, 0);\n return (true, a / b);\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n *\n * _Available since v3.4._\n */\n function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n if (b == 0) return (false, 0);\n return (true, a % b);\n }\n\n /**\n * @dev Returns the addition of two unsigned integers, reverting on\n * overflow.\n *\n * Counterpart to Solidity's `+` operator.\n *\n * Requirements:\n *\n * - Addition cannot overflow.\n */\n function add(uint256 a, uint256 b) internal pure returns (uint256) {\n uint256 c = a + b;\n require(c >= a, \"SafeMath: addition overflow\");\n return c;\n }\n\n /**\n * @dev Returns the subtraction of two unsigned integers, reverting on\n * overflow (when the result is negative).\n *\n * Counterpart to Solidity's `-` operator.\n *\n * Requirements:\n *\n * - Subtraction cannot overflow.\n */\n function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n require(b <= a, \"SafeMath: subtraction overflow\");\n return a - b;\n }\n\n /**\n * @dev Returns the multiplication of two unsigned integers, reverting on\n * overflow.\n *\n * Counterpart to Solidity's `*` operator.\n *\n * Requirements:\n *\n * - Multiplication cannot overflow.\n */\n function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n if (a == 0) return 0;\n uint256 c = a * b;\n require(c / a == b, \"SafeMath: multiplication overflow\");\n return c;\n }\n\n /**\n * @dev Returns the integer division of two unsigned integers, reverting on\n * division by zero. The result is rounded towards zero.\n *\n * Counterpart to Solidity's `/` operator. Note: this function uses a\n * `revert` opcode (which leaves remaining gas untouched) while Solidity\n * uses an invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function div(uint256 a, uint256 b) internal pure returns (uint256) {\n require(b > 0, \"SafeMath: division by zero\");\n return a / b;\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n * reverting when dividing by zero.\n *\n * Counterpart to Solidity's `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n require(b > 0, \"SafeMath: modulo by zero\");\n return a % b;\n }\n\n /**\n * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n * overflow (when the result is negative).\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {trySub}.\n *\n * Counterpart to Solidity's `-` operator.\n *\n * Requirements:\n *\n * - Subtraction cannot overflow.\n */\n function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n require(b <= a, errorMessage);\n return a - b;\n }\n\n /**\n * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n * division by zero. The result is rounded towards zero.\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {tryDiv}.\n *\n * Counterpart to Solidity's `/` operator. Note: this function uses a\n * `revert` opcode (which leaves remaining gas untouched) while Solidity\n * uses an invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n require(b > 0, errorMessage);\n return a / b;\n }\n\n /**\n * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n * reverting with custom message when dividing by zero.\n *\n * CAUTION: This function is deprecated because it requires allocating memory for the error\n * message unnecessarily. For custom revert reasons use {tryMod}.\n *\n * Counterpart to Solidity's `%` operator. This function uses a `revert`\n * opcode (which leaves remaining gas untouched) while Solidity uses an\n * invalid opcode to revert (consuming all remaining gas).\n *\n * Requirements:\n *\n * - The divisor cannot be zero.\n */\n function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n require(b > 0, errorMessage);\n return a % b;\n }\n}\n"
},
"@openzeppelin/contracts/token/ERC20/IERC20.sol": {
"content": "// SPDX-License-Identifier: MIT\n\npragma solidity >=0.6.0 <0.8.0;\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n /**\n * @dev Returns the amount of tokens in existence.\n */\n function totalSupply() external view returns (uint256);\n\n /**\n * @dev Returns the amount of tokens owned by `account`.\n */\n function balanceOf(address account) external view returns (uint256);\n\n /**\n * @dev Moves `amount` tokens from the caller's account to `recipient`.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transfer(address recipient, uint256 amount) external returns (bool);\n\n /**\n * @dev Returns the remaining number of tokens that `spender` will be\n * allowed to spend on behalf of `owner` through {transferFrom}. This is\n * zero by default.\n *\n * This value changes when {approve} or {transferFrom} are called.\n */\n function allowance(address owner, address spender) external view returns (uint256);\n\n /**\n * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * IMPORTANT: Beware that changing an allowance with this method brings the risk\n * that someone may use both the old and the new allowance by unfortunate\n * transaction ordering. One possible solution to mitigate this race\n * condition is to first reduce the spender's allowance to 0 and set the\n * desired value afterwards:\n * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n *\n * Emits an {Approval} event.\n */\n function approve(address spender, uint256 amount) external returns (bool);\n\n /**\n * @dev Moves `amount` tokens from `sender` to `recipient` using the\n * allowance mechanism. `amount` is then deducted from the caller's\n * allowance.\n *\n * Returns a boolean value indicating whether the operation succeeded.\n *\n * Emits a {Transfer} event.\n */\n function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\n /**\n * @dev Emitted when `value` tokens are moved from one account (`from`) to\n * another (`to`).\n *\n * Note that `value` may be zero.\n */\n event Transfer(address indexed from, address indexed to, uint256 value);\n\n /**\n * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n * a call to {approve}. `value` is the new allowance.\n */\n event Approval(address indexed owner, address indexed spender, uint256 value);\n}\n"
}
},
"settings": {
"remappings": [],
"optimizer": {
"enabled": true,
"runs": 200
},
"evmVersion": "istanbul",
"libraries": {},
"outputSelection": {
"*": {
"*": [
"evm.bytecode",
"evm.deployedBytecode",
"abi"
]
}
}
}
} |